Mr. McGuinness, a former commander of the Irish Republican Army (IRA) terror group, died on Monday aged 66, just weeks after stepping down as Deputy First Minister of Northern Ireland.
Crowds walk with coffin in Derry after death of ex-IRA Commander Martin McGuinnessWhere is St Columba's Chapel in Derry? "There are people who never got their answers", he said.
"Martin was a hero in life and a hero in death", he said. "A lot of people had gathered there waiting for the cortège to pass by before it reached Martin McGuinness's home".
His death prompted reactions from politicians and others who paid tribute to the Irish republican, who played a key role in negotiations which led to the signing of the Good Friday Agreement in 1998.
Mr McGuinness was a controversial figure throughout his life.
"However, as my noble friend Lord Trimble (former Ulster Unionist First Minister at Stormont) set out yesterday, he played an indispensable role in bringing the republican movement away from violence to peaceful and democratic means and to building a better Northern Ireland". Much work remains to be done and his passing comes at a time when we need to rededicate ourselves both to nurturing peace and to creating more prosperity for all our citizens.
Politicians from the United Kingdom and Ireland also praised Mr McGuinness's contribution to peace and reconciliation.
The North Antrim MP said he had gone from viewing Mr McGuinness as the "godfather of the IRA" to considering him a personal friend.
His statesmanship as deputy First Minister has been central to the success of the peace process over the last decade. The move saw the Executive collapse and a snap election triggered.
Mr McGuinness' funeral will be held in Derry city on Thursday afternoon.
West Belfast has always been known as the most Republican part of the city and is a stronghold of support for Sinn Fein.
It took place hours after crowds in Londonderry accompanied his coffin on his final journey home to his Bogside neighbourhood.
Mr Adams said that Mr McGuinness led the IRA when there was a war and then led the IRA into peace and that Mr McGuinness "genuinely believed in reconciliation, even if it made people uncomfortable".
"If unionism has anything to learn from Martin McGuinness it is the importance of outreach".
Tony Blair (l) meets Gerry Adams (c) and Martin McGuinness (r) in his parliamentary office in 2007.
He added: "It's been a very hard day for people here in Derry".
Priest Gary Donegan hailed Mr McGuinness' contribution to the peace process as he addressed the vigil.
Given his previous IRA activities, Martin had credibility with the rank-and-file militarists in the republican movement and this was deployed to quell charges of a sell-out as Sinn Féin first engaged in peace talks.